1. Field of the Invention
The present invention relates generally to a window blind assembly and more particularly, to a cord stopper which is detachably and slidably connectable to a lift cord of a window blind assembly.
2. Description of the Related Art
Window blind assemblies are intensively used to decorate windows and to shield windows from outside incident light. A window blind assembly constructed according to U.S. Pat. No. 6,453,974 is shown in FIG. 1, comprising a headrail 11, a bottom rail 12, a blind supporting system 13 joining the headrail 11 and the bottom rail 12 and mounted with a plurality of slats 14, two lift cords 15 each having a first portion 152 affixed to one end of the bottom rail 12 and upwardly penetrated through the slats 14 and the headrail 11 and a second portion 151 extended out of the headrail 11 through a lift cord lock 16 near one end of the headrail 11. The second portion 151 of each lift cord 15 is for pulling by the user to control the elevation of the bottom rail 12, i.e., changing the length of the second portion 151 of each lift cord 15 relatively control the extending (unfolding) status of the window blind assembly. A window blind assembly of this design is not safe in use. Because the first portion 152 of each lift cord 15 that passes through the slats 13 can easily be pulled by a child, and an accident may occur when a child playing with the first portion 152 of each lift cord 15 for fun and hang the first portion 152 of each lift cord 15 on the neck accidentally. Further, the lift cord lock 16 may fail, thereby causing the slats 14 and the bottom rail 12 to fall suddenly and to further hit a person below accidentally. In order to eliminate these problems, U.S. Pat. No. 6,453,974 uses two cord stoppers 17 to limit stretching of the first portion 152 of each lift cord 15. According to this design, each cord stopper comprises a locking guider having at least a guiding through slot provided thereon; each locking guider is slidably connected to the respective lift cord by tying an adjustable knot at the guiding through slot; the adjustable knot is constructed by tying the lift cord on the locking guider by forming a loop on the lift cord, passing the loop through the respective guiding through slot and penetrating a free end of the lift cord into the loop so as to form the adjustable knot tying around the locking guider, as shown in FIG. 2. This installation procedure is complicated and inconvenient.
Therefore, it is desirable to provide a window blind assembly having one or more cord stoppers that eliminate the aforesaid problem.